Ocular: Nasolacrimal System Flashcards
What is the purpose of the nasolacrimal system?
to drain tears from the ocular surface to the lacrimal sac
Where does the nasolacrimal system ultimately end?
Nasal cavity
What are the tears produced by?
Palpebral portion of the lacrimal gland
Where is the start of the nasolacrimal system?
Lacrimal gland in the superior lateral portion of the orbit
where is the end of the nasolacrimal system?
Inferior nasal meatus of the nasal cavity
Blockage of the nasolacrimal system can cause what?
Tears to overflow, called epiphora
What type of gland is the lacrimal gland?
Exocrine gland
Where is the aqueous portion of tears released into?
the fornix
Palpebral portion of the lacrimal gland contains ____ ducts. They come from _______ and _________ portions open into the _______
12 ducts, orbital and palpebral portions , fornix
What portion of the lacrimal gland is biopsies in lacrimal gland tumor? why?
Orbital portion in order to avoid ducts
What cells make up the lacrimal gland?
Many tiny acini cells
Acinar cells =
Merocrine secretory cells
What surrounds the acini?
Discontinuous ring of myoepithelial cells
What does the matrix around the acini cells contain?
-T cells
-B cells
-plasma cells
What vessels supply the lacrimal gland?
-lacrimal artery
-lacrimal vein
-lymphatics drains into into pre-auricular
Parasympathetic nerve supply to the lacrimal gland causes…
Production and release of aqueous tear compartment
Sympathetic nerve supply to the lacrimal glands controls…
Vascular tone within the gland
What provides sensory innervation to the lacrimal gland?
Lacrimal nerve of v1
Where does reflex or emotional tearing come from?
Main lacrimal gland
Where does basal tear production occur?
Accessory lacrimal glands (Wolfring and krause)
Order of the nasal drainage system:
-punctuated
-canaliculi
-lacrimal sac
-nasolacrimal duct
-valve of hasner
Can people’s canaliculi come together?
Yes
Canaliculi takes ___mm down (or up) and ___ mm across
2mm, 8mm
What are the puncta?
Tiny apertures where tears drain into the canaliculi